LOCATION MCGOWAN WA
Established Series
Rev. AG/TA/RWL
09/2019
MCGOWAN SERIES
Landscape--plateaus
Landform--ridges
Slope--2 to 15 percent
Parent material--colluvium and residuum derived from basalt with an influence of volcanic ash in upper part
Mean annual precipitation--about 1000 mm
Mean annual air temperature--about 8 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--mesic
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Vitrandic Haploxeralfs
TYPICAL PEDON: McGowan ashy loam, forested, on a 9-percent, southwest-facing slope at an elevation of 750 m
Oi--0 to 3 cm; needles, twigs, and leaves
A1--3 to 13 cm; ashy loam, light brown (7.5YR 6/4) dry, dark brown (7.5YR 3/4) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and common fine roots; many very fine irregular pores; 20 percent shotlike aggregates (1 to 2 mm); moderately acid (pH 6.0); clear smooth boundary
A2--13 to 28 cm; ashy loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; weak fine subangular blocky structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine and common fine roots; many very fine irregular pores; 10 percent shotlike aggregates (1 to 2 mm); moderately acid (pH 6.0); clear smooth boundary
BAt--28 to 41 cm; clay loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, common fine, and few medium roots; many fine irregular pores; 3 percent gravel; few faint clay films in pores; moderately acid (pH 5.8); clear smooth boundary
Bt1--41 to 69 cm; clay loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; many fine irregular pores and few fine tubular pores; 3 percent gravel; few faint clay films in pores; moderately acid (pH 5.8); gradual smooth boundary
Bt2--69 to 109 cm; clay loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and few fine and coarse roots; many fine irregular pores; 5 percent gravel; few distinct clay films on faces of peds and in pores; moderately acid (pH 5.9); clear smooth boundary
Bt3--109 to 155 cm; clay loam, brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and moderately plastic; few very fine roots; many fine irregular pores; 5 percent paragravel; few faint clay films on faces of peds and in pores; moderately acid (pH 5.8)
TYPE LOCATION: Klickitat County, Washington, about 11 km northwest of Lyle; about 245 m north and 550 m east of the southwest corner of section 29, T. 4 N., R. 12 E.; latitude 45 degrees, 48 minutes, 0 seconds north and longitude 121 degrees, 20 minutes, 6 seconds west
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 11 degrees C
Soil moisture control section--dry in all parts 45 to 60 consecutive days during the 4 months following summer solstice in 6 years or more out of 10 years
Content of clay in particle-size control section--18 to 33 percent
Base saturation--50 to 60 percent
Content of rock fragments in particle-size control section--0 to 10 percent gravel 2 to 4 mm in size
Content of rock fragments below a depth of 100 cm--0 to 20 percent paragravel, 0 to 15 percent gravel, 0 to 10 percent cobbles
Volcanic ash influence
*Thickness--18 to 35 cm
*Moist bulk density--1.10 to 1.30 g/cm3
*Content of volcanic glass--5 to 30 percent
*Acid oxalate Al plus 1/2 Fe--1 to 2 percent
*Phosphorus retention--50 to 75 percent
*15-bar water retention--8 to 12 percent
A horizon
Hue--5YR to 10YR
Value--4 to 6 dry
Chroma--2 to 4 dry or moist
Reaction--5.1 to 6.0
Combined thickness--18 to 25 cm
BAt horizon
Hue--5YR, 7.5YR
Value--4 to 6 dry, 3 or 4 moist
Chroma--3 or 4 dry or moist
Texture--ashy loam, loam, clay loam
Reaction--5.1 to 6.0
Thickness--13 to 41 cm
Bt horizon
Hue--5YR, 7.5YR
Value--4 to 6 dry, 3 or 4 moist
Chroma--4 to 6 dry or moist
Texture--dominantly loam or clay loam, but ranges to gravelly clay loam below a depth of 100 cm
Reaction--5.1 to 6.0
Combined thickness--76 to 150 cm or more
COMPETING SERIES:
Kephart--dry 90 to 130 consecutive days following summer solstice; A and C horizons that have 35 to 90 percent pumice paragravel
Lakespring--50 to 100 cm (moderately deep) to densic contact (lake sediment); dry 60 to 90 consecutive days following summer solstice
GEOGRAPHIC SETTING:
Elevation--185 to 790 m
Climate--warm, dry summers; cool, wet winters
Mean annual precipitation--890 to 1140 mm
Mean January air temperature--about -2 degrees C
Mean July air temperature--about 18 degrees C
Mean annual temperature--about 7 to 10 degrees C
Frost-free season--120 to 140 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Chemawa--ashy particle-size class; on terraces
Fanal--mollic epipedon; on hillslopes
Husum--ashy-skeletal particle-size class; on terraces
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high
USE AND VEGETATION:
Use--timber production, crop production, livestock grazing, wildlife habitat, some urban development
Principal crops--orchard crops, small grain, hay, pasture
Native vegetation--Douglas-fir, grand fir, vine maple, creambush oceanspray, cascade Oregon grape, common snowberry
DISTRIBUTION AND EXTENT: Klickitat County, Washington; MLRA 6; moderate extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Klickitat County, Washington; 2003
REMARKS:
Diagnostic horizons and other features in this pedon
*Ochric epipedon
*Argillic horizon--zone from 28 to 155 cm
*Particle-size control section--zone from 28 to 79 cm
*Vitrandic feature--zone from 3 to 28 cm
ADDITIONAL DATA:
Partial laboratory data--Kellogg Soil Survey Laboratory pedon numbers 40A0989, 40A0990, and 87P0056
National Cooperative Soil Survey
U.S.A.